Broad scale population estimates of declining species are desired for conservation efforts. However, for many secretive species including large carnivores, such estimates are often difficult. Based on published density estimates obtained through camera trapping, presence/absence data, and globally available predictive variables derived from satellite imagery, we modelled density and occurrence of a large carnivore, the jaguar, across the species’ entire range. We then combined these models in a hierarchical framework to estimate the total population. Our models indicate that potential jaguar density is best predicted by measures of primary productivity, with the highest densities in the most productive tropical habitats and a clear declining gradient with distance from the equator. Jaguar distribution, in contrast, is determined by the combined effects of human impacts and environmental factors: probability of jaguar occurrence increased with forest cover, mean temperature, and annual precipitation and declined with increases in human foot print index and human density. Probability of occurrence was also significantly higher for protected areas than outside of them. We estimated the world’s jaguar population at 173,000 (95% CI: 138,000–208,000) individuals, mostly concentrated in the Amazon Basin; elsewhere, populations tend to be small and fragmented. The high number of jaguars results from the large total area still occupied (almost 9 million km2) and low human densities (< 1 person/km2) coinciding with high primary productivity in the core area of jaguar range. Our results show the importance of protected areas for jaguar persistence. We conclude that combining modelling of density and distribution can reveal ecological patterns and processes at global scales, can provide robust estimates for use in species assessments, and can guide broad-scale conservation actions.
Female pattern polymorphisms (FPP) are striking, poorly understood, and a major challenge to evolutionary theory. We examined the evolution of FPP in anoline lizards in a phylogenetic context. Accordingly, we used comparative analyses that traced the evolution of female pattern polymorphism over historical time, and overlaid the historical pattern on the biogeographical distribution of current species. Comparative analyses used a maximum likelihood approach with variable rates of trait evolution. We found that, among almost 180 well-described species, 52 exhibited FPP and most of these occurred on the Central American mainland. Pagel's l = 0.644 indicated not only a moderately strong phylogenetic signal in FPP among 162 species with sound estimates of phylogeny, but also independent evolution. Their common ancestor was not polymorphic (0.003% likelihood of FPP), and there were at least 28 gains or losses of FPP during phylogenetic history. The geographical distribution of FPP indicates that, in the Caribbean islands, it has been present for almost 20 million years, and that parallel evolution of FPP has taken place during that time, including independent evolution on Cuba, Hispaniola, and Puerto Rico. Evidence of parallel evolution of FPP in anoles was fairly strong.
Understanding the distribution patterns of threatened species is central to conservation. The Amazonian distribution of the northern tiger cat (N-tiger cat, Leopardus tigrinus) and its interspecific relationship with the ocelot, its potential intraguild killer, are intriguing. Here, we combined presence/absence records with species distribution models (SDMs) to determine N-tiger cat occurrence in the Amazon. We also modeled ocelot density from 46 published estimates. The N-tiger cat’s presence in the Amazon was negatively influenced by ocelot density and net primary productivity and positively influenced by savannas and precipitation in the driest month. The best-fitting model predicted highly patchy N-tiger cat occurrence over an area of 236,238.67 km2, almost exclusively in savanna enclaves. Additionally, 312,348 camera trap-days at 49 sites in the Amazon revealed no N-tiger cats. The ocelot densities were significantly higher in areas with denser vegetation cover and warmer habitats, with predicted densities ≥ 0.6 ind/km2 throughout most of the biome. The lowest ocelot densities (≤ 0.06 ind/km2) were observed along the predicted range of N-tiger cats. Our findings highlight that the N-tiger cat’s presence in the Amazon is restricted to savannas and highly influenced by ocelot density, emphasizing the importance of including species interactions in SDMs.
We elucidate the value orientations (VOs) towards wild meat/wildlife in the Tshopo Province of the Democratic Republic of Congo, distinguishing between the provincial capital and rural areas. Based on stories prompted by four primary emotions, the most frequently encountered VOs were: concern for safety, nutrition and taste, and caring/respect. Rural people were more likely to express anthropocentric VOs. However, their stories did not necessarily associate negatively with caring/respect, suggesting that wildlife users may also be sensitive to biocentric values. Age, gender, and wealth were good predictors for biocentric VOs, with young women from the city more likely to express biocentric values. VOs and emotions related differently to specific wildlife species. Mutualism was not frequently elucidated in the stories. The associations we found provide crucial information to understand differences in value orientations across groups, identify barriers to change, and tailor behavior change campaigns to the local context.
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